Figure



July 16, 1963 A. c. AVRIL BAG CLOSING MACHINE Filed Aug. 21, 1961 6Sheets-Sheet l A TfOEA/EYZ July 16, 1963 A. c. AVRIL BAG CLOSING MACHINE6 Sheets-Sheet 2 Filed Aug. 21, 1961 INV NTOR. M 6.

July 16, 1963 A. c. AVRIL 3,097,461

BAG CLOSING MACHINE Filed Aug. 21, 1961 e Sheets-Sheet a ///ijigb .6 a&VE0R.

\1 13 ATTOBAEYS.

1oe 11s @0 4 hazamgam July 16, 1963 A. c. AVRIL BAG CLOSING MACHINE 6Sheets-Sheet 4 Filed Aug. 21, 1961 JXAWMM AT TORNEY5.

July 16, 1963 A. c. AVRIL BAG CLOSING MACHINE 6 Sheets-Sheet 5 FiledAug. 21, 1961 ATTOkA/Ef July 16, 1963 A. c. AVRIL BAG CLOSING MACHINE 6Sheets-Sheet 6 Filed Aug. 21, 1961 Mid/M. 14 T TOZA/Effi United StatesPatent 3,997,461 BAG CLOSlNG MACHlNE Arthur C. Avril, Wyoming, Ohio,assiguor to A & T Development Corporation, Cincinnati, Ohio, acorporation of Ohio Filed Aug. 21, 1961, Ser. No. 132,879 5 Claims.(ill. 53-137) This invention relates to bag closing machines of the typewhich fold a strip of tape across the open end of a filled bag andthereafter apply a line of stitching through the over-folded tape andbag to seal the contents therein.

The present invention is directed to improvements in bag closingmachines of this general character, wherein the bag is formed ofrelatively heavy paper or fibrous material, the tape being formed ofgenerally similar material. The bag filling and closing machineincorporating the present improvements, is intended particularly forpackaging granulated materials and is disclosed in relation to thepackaging of dry, pre-mixed building materials, for example, dry,pre-mixed concrete consisting of a mixture of dehydrated sand, aggregateand Portland cement. This material is prepared in a processing plantwhich dehydrates the sand and aggregate, mixes the materials with drycement in predetermined proportions, then discharges the mixture inbatch fashion into moisture repellent paper bags. A processing plant ofthis character is disclosed in the prior patent of Arthur C. Avril, No.2,904,942. After being filled, the bag is sealed by the bag closingmachine and is ready for storage and sale to the purchaser. It will beunderstood that the present bag closing apparatus is intended forpackaging various other types of granulated material in conjunction withappropriate packaging plants wherein successive batches of material areloaded into bags which are subsequently sealed in a rapid manner by thebag closing machine.

A typical bag closing machine of the type to which the presentimprovements are directed, essentially comprises a bag conveyor and astitching machine or head. The empty bags are placed upon the conveyorbeneath the discharge spout of the processing plant by an operator whoregulates the cycles of the processing plant and bag closing machine.After the material is discharged from the chute into the bag, theconveyor is operated to advance the filled bag toward the stitchingmachine, which is located above the conveyor in a position to act uponthe upper portion of the bag.

As the upper portion of the bag advances into the stitching machine orhead, it passes beneath and is embraced by a strip of tape which ispartially doubled across the upper end of the bag which has been foldedto a closed position. Upon further advancement by the conveyor, theupper portion of the bag trips a control device which energizes themotor of the stitching machine, causing it to apply a line of lockstitching through the doubled-over tape and upper portion of the bag,thus sealing the contents within the package.

As the trailing edge of the bag passes beyond the control device, thestitching machine is 'deenergized, then a trimming device, regulated bya sensing element which is tripped by the trailing edge of the bag,severs the tape which trails from the bag. However, due to inertiaacting on the moving parts of the machine, the bag advances asubstantial distance, for example, six to eight inches be yond thetrimming device before the tape can be severed. Accordingly, in theoperation of a conventional machine, each bag is discharged from the bagclosing machine with this length of waste tape extending from itstrailing side. Since the material is packaged at a high production rate,the amount of tape thus wasted during a days run represents a veryconsiderable expense item.

3,097,461 ed J y 1 .953

2 One of the primary objectives of the present invention has been tosubstantially eliminate the waste of 1 6 without essentially changingthe conventional stitching machine, by providing a motor which includesbraking apparatus arranged to bring the stitching machine abruptly to astop as the trailing edge of the bag passes beyond the control deviceand sensing element of the trimming device. According to this \aspect ofthe invention, the brake stops the motor as soon as the motor circuit isdeenergized, thereby to stop the stitching head and to prevent thetrailing side of the bag from advancing very far beyond the sensingelement of the trimming device. The sensing element thus is tripped tocause operation of the tape trimming device after the trailing edge ofthe bag advances a predetermined distance beyond the trimming device,thereby to control the amount of waste tape which trails from the bag.Briefly therefore, by applying the braketype motor to the conventionalmachine, in accordance with the principles of this invention, the wasteof tape at the cut-off operation is substantially eliminated without anychange in the stitching and tape trimming mechanisms. A furtherobjective of the invention has. been to im; prove the sensitivity of thecontrol device which starts and stops the motor of the stitching machinein response to the advancement of the bag, thereby to further impnovethe accuracy of the tape trimming operation. 7 i Briefly, the brake-typemotor is energized by a normally open micro-switch, which is actuated bya trip bar mounted in a position to intercept an advancing bag, therebyto close the switch and energize the motor. The trip bar is pivotallymounted for motion in a path transverse to the line of advancement ofthe bag, the pivotal axis being disposed below the trip bar. Thearrangement is such that the bar is tripped with very little resistanceby the leading edge of the advancing bag to close the switch forenergizing the motor; the bar also responds quickly to the passage ofthe trailing edge of the bag so as to deenergize and brake the motorwith very little lag, thereby to increase the sensitivity of the controlsystem and further reduce the wastage of tape. Still another objectiveof the invention has been to improve the mounting structure of thestitching head and conveyor so as to adapt the. machine to be adjustedconveniently to suit various bag sizes and also to allow the workingparts to be adjusted relative to the fioorle vel to compensate for theheight of the operator.

In general, the mounting structure comprises a base having a verticalcolumn, the stitching head and con- 'veyor structure both being mountedupon the column, one above the other. In order to provide adjustment toaccommodate for the 'bag sizes, the column includes a vertical rack, theconveyor and stitching head being slidably mounted upon the column andeach including a duplicate self-locking adjustment mechanism, includinga pinion meshing with the rack and adjusted by a worm and worm wheeldrive. Accordingly the conveyor may be raised or lowered conveniently asa unit relative to the delivery chute to compensate for the height ofthe operator; while the stitching head, in a similar manner, may beadjusted along the column to locate the line of stitching accuratelywith respect to the upper portion of the bag which rests upon theconveyor. In order to stabilize the assembly, the conveyor structure,which extends outwardly from opposite sides of the column, includesextensible posts which are jadjusted to engage the floor surface afterthe conveyor has been shifted to the desired elevation by theselflocking adjustment mechanism. The conveyor structure thus acts as anelongated base which firmly stabilizes the entire machine with referenceto the floor surface. The various features and advantages of theinvention spa m will be more fully apparent to those skilled in the artfrom the following description, taken in conjunction with the drawings.

In the drawings:

FIGURE 1 is a front elevation of a bag filling and closing machineembodying the present improvements.

FIGURE 2 is an end view of the machine, as projected from FIGURE 1.

FIGURE 3 is a fragmentary perspective view, particularly illustratingthe bag stitching head.

FIGURE 4 is an enlarged fragmentary view taken along line 44 of FIGURE2, illustrating the switchactuating trip bar for regulating theoperation of the stitching head.

FIGURE 5 is a sectional view taken along line 5-5 of FIGURE 4, furtherillustrating the switch-actuating mechanism.

FIGURE 6 is a bottom plan, as viewed along line 6-6 of FIGURE 5, furtherdetailing the switch-actuating mechanism.

FIGURE 7 is an enlarged fragmentary view taken along line 7-7 of FIGURE1, showing the switch-actuating mechanism in its normal position withthe stitching head deenergized.

FIGURE 8 is a view similar to FIGURE 7, showing the switch-actuatingmechanism tripped by an advancing bag to energize the stitching head.

FIGURE 9 is a diagrammatic view showing the upper portion of a stitchedbag and the relationship of the switch-actuating mechanism and tapesevering device.

FIGURE 10 is a view similar to FIGURE 9, but showing a length of tapetrailing from the bag as an example of the operation of a bag closingmachine which is not equipped with the present improvements.

FIGURE 11 is a sectional View taken along line 1111 of FIGURE 1,illustrating the adjustment mechanism for locating the stitching head atthe proper elevation with respect to the top portion of the filled bag.

FIGURE 12 is a fragmentary side elevation, as viewed along line -1212 ofFIGURE 11, further illustrating the head adjustment mechanism.

FIGURE 13 is an end view of the adjustment mechanism taken along line1313 of FIGURE 12.

FIGURE 14 is a fragmentary view similar to FIGURE 12, showing theopposite side of the adjustment mechamsm.

FIGURE 15 is a sectional view taken along line 1515 of FIGURE -1,illustrating the conveyor system which advances the bags from thefilling station through the stitching head.

FIGURE 16 is a diagram illustrating an electrical circuit for regulatingthe machine.

Structure and Operation Generally As noted above, the bag filling andclosing machine of the present invention is intended for the packagingof granulated materials generally, and is particularly adapted to thepackaging of dry, premixed building materials, such as plaster mix,mortar mix, dry concrete mix, and the like. The machine is intended tobe operated in conjunction with the processing plant which prepares andmeters the material in batchestor discharge into individual containersor bags. t

The plant for dehydrating and discharging batches of dry concretemixture, disclosed in the above noted patent to Arthur C. Avril,2,904,942, presents a typical example of a processing apparatus withwhich the bag filling and closing machine of this invention may be used.As disclosed in this patent, the apparatus dehyd'rates the sand andaggregate or gravel by heat exchange principle, wherein the sand isfirst heated to a predetermined temperat-ure (and dried), then iscommingled with the raw, moist gravel. The heated sand thus drives oifthe moisture from the gravel by heat exchange, then metered quanti- 4ties of dehydrated sand, dehydrated gravel and dry Portland cement aremixed and discharged in the form of individual batches intomoisture-resistant paper bags while still warm. The exchange of heatbetween the hot sand and raw gravel not only dehydrate the gravel, butalso reduces the mixture to a safe bagging temperature, adapting themixture to be discharged immediately into the bags. In other words, thedischarge temperature is sufficiently low to prevent damage to thefibers of the paper bags but is sufficiently high to prevent the mixturefrom reabsorbing moisture from the air after discharge and prior topackaging.

Referring to FIGURES 1 and 2, the chute indicated at 1 represents thedelivery point of the processing machine with which the present baggingapparatus may be utilized. Described with reference to the Avrildehydration apparatus of'the prior patent referred to above, the cyclesof operation preferably are controlled by an operator who places anempty bag 2 on the belt conveyor, indicated generally at 3. The conveyorsupports the bag in position beneath the chute to receive the dryconcrete mixture, indicated at 4, as it issues from the chute. With thebag thus positioned, a prepared batch of dry concrete mix is dischargedby gravity from the chute to the bag upon operation of a control switchby the operation. After the batch of dry concrete mix is delivered tothe bag, the operator releases a treadle 5, which energizes the conveyormotor 6 (FIGURE 15), causing the bag to be advanced by the belt conveyorfrom the loading station to the stitching head, which is indicatedgenerally at 7'. As the bag approaches the stitching head, its upperportion engages a trip bar 8 (FIGURE 2) which energizes the motor 10 ofthe stitching head. This motor is a commercial product and includes abuilt-in brake which stops the motor immediately when the circuit isopened.

It will be understood at this point, that the stitching head 7 is also acommercial product and has not been disclosed in detail since itsstructural features, with certain exceptions as pointed out later, donot form a part of the present invention. The head includes the usualfeed mechanism which advances the bag in time with the reciprocations ofthe needle and shuttle. However, the feed mechanism of the stitchinghead is not capable of advancing the heavily-loaded bag during thestitching operation; therefore, the conveyor motor 6, and the stitchinghead motor 10 are arranged to drive the conveyor belt and stitchingmechanism in synchronism with one another. In other Words, the bag isadvanced by the conveyor 3 at the same rate as the feeding mechanism ofthe stitching head advances the upper portion of the bag; hence, thereis no strain between the stitching mechanism and upper portion of thebag.

During the stitching operation, a strip of tape 11 (FIG- URE l) is fedalong with the bag, the tape being doubled over the upper end of thebag, .as explained later, then a line of lock stitching 12 (FIGURES 9and 10) is applied through the over-folded tape and upper portion of thebag, thereby sealing the filled package. After the trailing end of thebag passes beyond the end of the trip bar 8, the stitcher motor 10 isdeenergized and braked immediately to a stop; at about the same time, atrimming device, indicated diagrammatically at 13 (FIGURE 9), severs thetape as at 14, at a point slightly beyond the trailing edge of the bag.It will be understood that the conveyor 3 continues advancing the bagduring the stitching and tape trimming operations.

The filling and closing mechanism is intended to operate at a rapidrate, whereby successive bags may be filled and guided through thestitching machine by an individual operator, then advanced preferably toa second operator downstream from the stitching head who unloads thefinished package from the conveyor. For this purpose, the treadle 5 isarranged to energize the conveyor motor 6 continuously, except when thetreadle is depressed by the operator. On the other hand, the motor 10,which drives the stitching head, is energized only when the upperportion of the bag engages the trip bar 3, as noted above.

In operation therefore, the operator depresses the treadle to deenergizeconveyor motor 6, thereby to hold the bag in stationary position beneaththe chute 1 during the filling operation. After the bag is filled, theoperator releases the treadle to energize the conveyor motor; theoperator therefore is free to follow the advancing bag while graspingits upper portion to bring it properly into the guiding mechanism of thestitching head, a explained later. The conveyor continues advancingduring the stitching and tape trimming operation, at which point thestitching head is braked to a stop. Thereafter, the bag (with the tapesevered) is free to advance until the operator returns to the loadingstation and depresses the treadle, thereby stopping the conveyor for thenext bag loading and stitching cycle.

As viewed in FIGURES 1 and 2, the stitching head 7 is mounted upon acolumn 15 rising upwardly from a base 16 which rests upon the floor. Inorder to adapt the closing machine to the various ibag sizes, thestitching 'head i connected to the column 15 through a self-lockingadjustment mechanism, which is generally indicated at 117. Theadjustment mechanism permits the stitching head to be raised or loweredwith respect to the surface of conveyor 3 so as to locate the line ofstitching 12 accurately with respect to the upper portion of the bag.

The conveyor 3 is also mounted :for vertical adjustment with respect tothe column 15 by means of a second adjustment mechanism, indicatedgenerally at 18 in FIGURE 2. This mechanism is similar to the adjustmentmechanism 17, thus bringing about a saving in fabrication costs. Thesecond adjustment mechanism permits the conveyor to be adjustedvertically with respect to the floor level for the convenience of theoperator, since it is extremely tiring to handle bags for prolongedperiods with the conveyor too high or too low. The conveyor adjustmentalso accommodates for the height of the bag with reference to the lowerend of the discharge chute 1 (FIGURE 1). It will be understood that theheight of the stitching head is adjusted after the conveyor adjustmentis made in order to properly locate the line of stitching .12 withreference to the upper portion of the bag. The two adjustment mechanism17 and 18 thus adapt the machine to the filling and closing of thevarious types and sizes of bags.

The conveyor includes pairs of extensible posts or jacks 20, which arearranged to be extended or retracted so as to engage the floor, therebyto stabilize both ends of the conveyor in its adjusted position. Themounting structure of the conveyor motor 6 also includes an extensiblepost 21 (FIGURE 2), which is similarly adjusted with reference to thefloor level for stabilizing the structure. The posts 20 and 21 bothinclude clamping elements 19 for locking the posts rigidly inadjustment.

Bag Conveyor As explained above, the conveyor 3 and stitching head 7 areboth sup-ported upon the vertical column 15, which rises from the base16. The base 16 consists of a channel iron structure suitably weldedtogether (FIG- URE 15), comprising channel irons 22-22 and 23-23 whichextend diagonally with respect to the longitudinal axis of the conveyor.it will be noted that the channel irons 23 are substantially longer thanthe irons 22 in order to compensate for the overhanging weight load ofthe conveyor. The column is joined to the channelirons by a compositebase plate structure 24 which may be welded to the channel irons uponwhich it rests.

The adjustment mechanism of the conveyor, previously indicated at 18,includes a vertically shiftable carriage structure, indicated generallyat 25, having a sleeve portion 26 'slidably embracing the column 15 andsupporting the conveyor 3. The lower portion of the sleeve has amounting plate 27 upon which is mounted the conveyor motor 6. Themounting plate 27 is braced with respect to the sleeve by a gusset plate28 joined to the parts by welding.

The adjustment mechanism 18 of the conveyor is described in relation tothe adjustment mechanism 17 of the stitching head (FIGURES 11-14) sinceboth units 17 and 18 are in duplicate. Each adjustment mechanismcomp-rises a pinion 30 keyed to a stub shaft 31,

the stub shaft having its opposite end portions journalled in bearingbrackets 32-62, which project outwardly from the sleeve 26 of theconveyor carriage (or [from the sleeve 41 of the stitching head, asnoted later). The pinion 30 meshes with a vertical rack 33, which issecured to and coextensive with the column 15. The sleeve 26 includes abridging section 26a (FIGURE 2) passing across the rack 33' to reinforcethe sleeve. The stitcher head sleeve 41 includes a similar bridgingsection 41a.

As best shown in FIGURES 1*l-14, shaft 31 includes a worm wheel 34 whichis keyed to the shaft 31 adjacent the pinion 30. A worm 35 meshes withthe worm wheel and is rotatably journalled between a pair of bearinglugs 36-36 (FIGURE 11) which are secured to one of the bearing brackets32. The worm includes an outwardly projecting stub shaft, including asquared end 37 providing wrench engagement for rotating the Worm when itis necessary to adjust the elevation of the conveyor. It will be seenthat the worm and Worm wheel provide a self-locking drive, such that theconveyor assembly will remain at any plane to which it is adjusted.However, as noted earlier, the structure includes extensible posts 20and 21 which are shifted into engagement with the floor so as tostabilize the conveyor structure and also to rigidi-fy the entiremachine with respect to the floor upon which the machine is resting.

The adjustment mechanism 17 for the stitching head does not include theposts 20 and 21; instead, a clamp screw 38 (FIGURES l1 and 14) isprovided. for clamping the assembly rigidly to the column 15. The screw38 is threaded through a bracket 40 which is welded to the sleeve 41 ofthe stitching head. The outer end of the clamp screw 38 includes a head42 providing a hand grip for turning the screw, while its inner endengages a disk 43 seated in an opening formed in the sleeve 41, the diskbeing forced under pressure into engagement with the column 15 to clampthe stitcher head at its adjusted elevation.

The conveyor 6 consists of a longitudinal frame, indicated generally at44 (FIGURES l, 2 and 1-5 comprising a pair of spaced longitudinal angleirons 4545, connected together by cross members 46. The cross membersproject transversely from a vertical plate 47 which forms a part of thesleeve 26, land which extends longitudinally from opposite sides of thesleeve' As shown in FIGURE 15, the vertical plate 47 is braced by ahorizontal plate 48, also extending longitudinally from opposite sidesof the sleeve. The conveyor frame structure includes a series ofdiagonal braces 50 (FIGURE 2) which extend in an upwardly inclined planefrom the vertical plate 47 to the outer angle iron 45 of the conveyorframe, thereby providing a rigid structure.

The conveyor frame 44 includes a flat platform 51 (FIGURE 1) restingupon the cross members 46 and slidably supporting the upper run of anendless belt 52.

A vertical guide plate49 rises upwardly from the :frame 44 parallelwith'the inner edge of the endless belt 52. The guide plate 49 isadapted to slidably support the filled bags in upright position in theevent that the bag should slip from the operators grasp. The belt istracked at topposite ends upon a drive roller 53 and an idler roller 54(FIGURE 1) mounted on cross shafts 55 and 56 journalled at opposite endsof the conveyor frame 44. The cross shaft 55 comprises a power shaft andis journalled in bearings 57 at opposite sides of the frame, thebearings 7 being supported by fixed brackets 58 projecting from the endof the frame at opposite sides.

The shaft 56 of the idler roller 54 is similarly journalled in bearings57 at opposite sides of the frame. However, in this case, the bearingsare mounted upon adjustable brackets 6tl-6tl (FIGURES 1 and .15) toprovide adjustment of the belt 52. For this purpose, each bracketincludes bolts 6161 projecting outwardly through slots 6262 formed inthe angle irons 45, the bolts including clamping nuts 63. Each bracket60 includes a lug 64 projecting outwardly through the rearward slot 62.An adjustment screw 65 for each adjustment bracket, is threaded througha lug 66, fixed to the conveyor frame, and has its end in engagementwith the lug 64 of the adjustment bracket. The adjustment screws 65 maybe rotated to tighten the endless belt, after which the nuts 63 aretightened to clamp the brackets 60 in adjusted position.

The drive roller 53 is powered by the conveyor motor 6 (FIGURE 15) whichis supported by the mounting plate 27 carried by the sleeve 26, asexplained earlier. The motor 6 includes a gear head 67 of conventionaldesign, including a speed reduction drive shaft 68. A pulley 70 ismounted on shaft 68, and a companion pulley 71 is mounted on the shaft55 of the drive roller 53. A V-belt 72 interconnects the pulleys 70 and71 so as to drive the conveyor belt in the direction indicated by thearrow. The pulleys 70 and 7 1 may be of the adjustable type, whereby therate of advancement of the conveyor belt is accurately regulated.

The motor 6 includes a base 73 (FIGURE 15), shifta'bly connected to themounting plate 27 by clamping bolts (not shown) in order to adjust theV-belt 72. The belt is tensioned by means of adjustment screws 74-74threaded through a plate 75 joined to mounting plate 27, the inner endsof the screws engaging the motor base 73 and including lock nuts 76. Inorder to tighten the belt 72, the mounting bolts are loosened, then thescrews 74 are adjusted in a direction to shift the motor inbelttightening direction.

It will be understood that the conveyor frame 44 and motor mountingplate 27 form a rigid structure which is raised or lowered as a unitrelative to the column by operation of the adjustment mechanism 18. Asnoted earlier, operation of the conveyor motor is controlled by thetreadle which is depressed to stop the motor so that the operator mayfollow the filled bag as it advances toward the stitching head.

Stitching Head and Tape Trimming Mechanism As is best shown in FIGURE 2,the stitching head 7 is generally in the form of an inverted U-s'hapedstructure having a vertical foot portion 77, enclosing the feedmechanism, and an outwardly spaced stitching unit 78 enclosing themechanism which reciprocates the needle 80'. The needle is mounted in aneedle bar 81 slidably mounted in the stitching unit 78. Since the feedand needle driving mechanisms are conventional, they have been omittedfrom the disclosure.

The stitching head is driven by the motor 10, previously noted, which isattached to a mounting plate 82 (FIG- URE 1), which projects outwardlyfrom the sleeve 41 of the stitching head. As best shown in FIGURE 11,the mounting plate 8'2 is slotted as at 83, the motor being secured tothe plate by bolts 84 passing through the slots 83 and into the base 85of the motor. In order to provide belt adjustment, mounting plate 82includes a lug 86 through which is threaded an adjustment screw 87engageable with the motor base 85.

The motor includes an adjustable V-belt pulley 88 (FIGURES 1, 2 and 11)connected by a belt 90 with the pulley 91 which drives the stitchinghead 7. The pulley 88 is of conventional design and provides variablepitch diameter in order to synchronize the speed of the stitching headwith the rate of advancement of the bag conveyor 3, as noted earlier. Ingeneral, the adjustable pulley 88 is of split construction, having asection or sections which may be shifted axially along the shaft of themotor to regulate the speed of the stitching head. In making thisadjustment, the screws 84 are loosened, the pulley pitch is regulated,then the adjustment screw 87 is rotated so as to shift the motor in adirection to maintain the belt 98 under proper tension, thereby toaccommodate for the adjustment of pulley 88.

As viewed in FIGURE '11, the stitching head 7 is attached to themounting plate 82 by means of clamp plates '92 which are secured tomounting plate 82 by screws 93. The plates 92 overlie the outwardlyprojecting base portions 94 of the stitching head, the screws 93including spacers 85. The arrangement is such that the plates 92 firmlyclamp the stitching head to the mounting plate 82.

As viewed in FIGURE 3, the stitching thread or cord 96 is supplied tothe needle from a spool (not shown), and a similar cord 97 is suppliedfrom a second spool to the shuttle in the conventional manner. Thesupply of tape 11, is also fed to the machine from an overhead reel (notshown). The tape consists of a heavy grade of paper or similar fibrousmaterial which is preferably crinkled transversely to impartflexibility. As noted earlier, the tape is fed through the machine intime with the bag and is doubled over the open end of the bag as itadvances toward the reciprocating needle, such that the line ofstitching 12 secures the tape in overlapped relationship across the openend of the bag, as shown in FIGURES 8lb.

The tape passes into the stitching head in the direction of advancementof the bags, as indicated by the arrows in FIGURE 3. In order to foldthe tape over the open end of the bag, the stitching head is providedwith a tape folding device which is indicated generally at 98. The tapefolding device 98 is mounted upon a pair of spacer bars ltltl1tltlprojecting outwardly from a bracket 181 which forms a part of themounting plate 82.

The tape folding device 98 is also conventional and has not beendisclosed in detail. In general, the folding device comprises anelongated forming rail structure, indicated generally at 182, projectinghorizontally from the stitching head and including at its outer end aguide roller 103 arranged to direct the tape into the end of the rail102. The forming rail structure, in cross section, delineates apassageway which converges progressively from its receiving end,indicated at 104, toward the stitching machine. As the bag is advancedby the conveyor, its upper portion passes into the passageway of railstructure 182 below the tape. The tape, which is stationary at thispoint, is folded generally to an inverted V-shape converging toward thestitching head, as delineated by the forming rail structure 162, suchthat the open end portion of the bag is enclosed progressively by theconverging folded tape as the bag advances. The forming rail structure102 includes a converging guide bar 105 which slidably engages theportion of the bag below the forming rail structure, so as to aid inclosing the upper portion of the bag as it advances.

As the bag enters the stitching head, its leading edge engages the tripbar 8 (FIGURES 7 and 8), so as to shift the bar transversely andenergize the motor 10, thus actuating the stitching head. At this point,the leading portion of the tape, which is engaged by the feed mechanismof the stitching head, is advanced by the feed mechanism, while the bagproper is being advanced by the conveyor 3, such that the bag advanceswith the overfolded tape toward the reciprocating needle 80. As the bagadvances with the over-folded tape, it encounters an outwardly flaredhorizontal guide plate 106 (FIGURES 3, 7 and 8), which coacts with thefeed mechanism to hold the tape and bag in assembled relationship, whilethe needle 86 applies the line of lock stitching 12.

As described in detail in (FIGURES 4-9), the trip bar 8 is partiallycylindrical in cross section and includes a receiving end 107 disposedadjacent the receiving end of the guide plate 106. The receiving end 107flares out- Wardly in a direction opposite to the receiving end of guideplate 106, so as to provide a converging throat for directing the upperportion of the advancing bag toward the needle of the stitching machine.The trip bar 3 is pivotally mounted upon a rock shaft 108 carried by abracket 11% which depends downwardly from a mounting plate 111. Themounting plate 111 is secured to the lower surface of the stitching headfoot 77 by screws.

The trip 'bar 8 includes a straight portion 112 which blends with theflared receiving end 107, and the straight portion includes a pair ofdownwardly projecting lugs 113 attached by screws 114 to the trip bar,The rock shaft 108 includes a torsion spring 115, having one endanchored in a collar 116 atfixed to the rock shaft, the spring having anopposite end portion 117 engaging one of the lugs 113 (FIGURE 6). Thearrangement is such that the spring 115 normally biases the trip bar tothe position shown in FIGURE 7, adapting the trip bar to be swung in thedirection indicated by the arrow in FIGURE 8 upon being slidably engagedby the advancing bag. In order to provide a backing, adapting the upperportion of the bag to actuate the trip bar 8, there is provided a fixedhorizontal guide rail 109, which is supported by a bracket 119 attachedto the stitching head by screws (FIGURE 2). The guide rail 109 ismounted in a plane below and coextensive with the guide plate 1116, in aposition to engage the upper flexible portion of thebag to prevent itfrom being defiected laterally by the spring-biased trip bar 3, therebyto insure positive operation of the bar.

As the trip bar is shifted to its tripped position (FIG- URE 8), one ofits lugs 113 engages and depresses the stem 113 of a micro-switch 120,which is also attached to the mounting plate 111. Upon being actuated,the microswitch completes a circuit which releases the brake of thestitching head motor 10, at the same time energizing the motor, asexplained later with reference to FIGURE 16. The stitching headcontinues to run until the trailing edge of the bag passes beyond theend 121 (FIGURE 6) of the trip bar. At this point, the motor 19 isdeenergized and the motor brake is applied so as to'stop the stitchinghead abruptly. At about the same time the tape trimming apparatus isactuated so as to trim on the tape at the trailing edge of the bag(FIGURE 9) from the length of tape which remains engaged by the feedmechanism of the stitching head, as explained in greater detail below.

, The tape trimming or out-oif mechanism forms a part of the stitchinghead and has not been disclosed in detail. As shown diagrammatically inFIGURE 9, the trimming mechanism, in general, comprises a spring-biasedsensing finger 122 which engages the upper portion of the bag beneaththe tape, and the trimming device, previously indicated at 13, which ismounted in a position to sever the tape ata point downstream from thesensing finger 122 in the direction of the bag movement. Thetrailing end1211 of the trip bar 8- is located in relation to the sensing finger, asindicated in FIGURE 9. Thus, as the trailing edge of the bag passesbeyond the end 121 of the trip bar, the spring-biased trip bar snaps toits normal position (FIGURE 7) so as to bring the stitching head to anabrupt stop. The brakin action substantially eliminates momentum, suchthat the bag travels only slightly beyond the end of the trip bar, asindicated by the clearance 124 in FIGURE 9.

The sensing finger 12 2 is interconnected with a mechanism (not shown)which forms a part of the stitching head, and which actuates the cutteror trimming device 13- as soon as the edge of the bag passes beyond thesensing finger. The relationship of the sensing finger 122 and end 121of the trip bar is such that the trimming device is actuated to trim thetape at about the same time the stitching head is braked to a stop. Thesensing finger 122 10 and trimming device 13 are enclosed in a housing123 (FIGURE 3) which is attached to the stitching head.

It will be understood at this point, that the trip bar 8 and the braketype motor 10 coast with one anotherto provide precise control of thestitching head and also adapt the conventional stitching machine tobring about a significant reduction in the amount of tape which iswasted at the trailing edge of the bag, as shown in FIG- URE 10. Inother words, in a stitching machine which is not equipped with asensitive trip bar 8 and brake-type motor, the inertia of the movingparts causes the trailing edge of the bag to advance at relatively highvelocity "beyond the trimming device '13 by reason of the inherent lagwhich occurs between the actuation of the sensing finger 122 andoperation of the trimming device 13. Accordingly, the present structureeliminates the length of tape 126 (FIGURE 10) extending beyond the trimline 14, which represents a typical example of the waste which occursdue to overrunning of a conventional stitching machine which is notequipped with the present improvements.

It will be understood that in some instances it is not necessary toapply a tape to the end of the bag, that is, the line 'of stitching isapplied directly to the bag itself. In this event, the machine is usedin the same manner, with no changes in structure except that the supplyof tape is omitted. At the end of each stitching operation the apparatusoperates in the manner described above to trim the line of stitching atthe trailing edge of the bag.

Electrical Control Circuit V The diagram shown in FIGURE 16 represents,in a simplified form, a typical electrical circuit suitable forcontrolling the apparatus of this invention. The block indicated at 127represents the control system, including electrical relays and othercomponents which regulate the operation of the conveyor motor 6 and themotor '10 of the stitching head. Power is supplied to the control system127 by the power lines 128 under control of the treadle, indicateddiagrammatically at *5. The treadle operates 'a normally-closed switch130' interposed in one of the branch lines 131. The branch lines 131 andswitch 130 c0mplete the power circuit from the control system 127 to themotors 6 and 10. In other words, the conveyor motor 6 isnormallyenergized and is deenergize d only when the treadle 5 isdepressed. On the other hand, the stitching head motor 10' also can beenergized only when the treadle is released, the circuit being completedthrough the normally-open micro-switch 120*. "When the machine is shutdown, thepower circuit 128 is deenergized by opening themanually-operated switch 129. I

The conveyor motor 6 is'energized by the branch lines 132 which areinterconnected with the power supply lines 133 leading from the controlsystem. The supply lines 133 are also interconnected with the stitchermotor 10 by way of the branch lines 134. Themicro-switch, previouslyindicated at 120, is of the normally opentype and isinterfrosed in oneof the branch lines 134 leading to the stitcher motor 10, thearrangement being such that the motor is energized only when anadvancing bag engages the trip bar 8 to close the switch 120.

As shown diagrammatically in FIGURE 16, the brake of the stitcher motor10 may be of the friction type, comprising a brake drum 135 mounted onthe motor shaft 136 and engaged by a brake shoe 137. The brake shoe 137,in the example illustrated, is normally forced into engagement with thedrum 135 by a tension spring 138 connected to a lever 140 which actuatesthe shoe. The brake is released by means of a solenoid coil 141connected in series with one of the branch lines 134 and having anarmature 142 connected with the brake lever 140.

Under normal operation, the normally closed treadle switch 130 energizesthe conveyor motor and thus causes the bag to be advanced toward thestitching: head by the belt conveyor 3, the stitcher motor 10 normallybeing deenergized by operation of the normally-open micro switch 120.When the bag engages the trip bar 8, it closes the micro-switch 120 andthus simultaneously energizes the stitcher motor 10 and the solenoidcoil 141 so as to release the brake and concurrently drive the motor.When the trailing edge of the bag advances beyond the end of the tripbar 8, the solenoid 141 and motor 10 are deenergized, adapting thespring 138 to apply the brake and thus bring the motor 10 abruptly to astop, as explained above.

Having described my invention, I claim:

1. A bag closing machine comprising, a base, a vertical column risingfrom said base, a vertical rack mounted on said column, a conveyorstructure slidably connected to said column, self-locking conveyoradjustment means on said conveyor structure including a pinion meshingwith said rack, a chute mounted above said conveyor and adapted todischarge material into the open end of a bag resting upon the conveyor,a bag stitching head mounted upon said column above the conveyor, saidstitching head adapted to fold a strip of tape over the open upperportion of the filled bag and to apply a line of stitching through saidtape and through the upper portion of the filled bag advancing on theconveyor, said conveyor adjustment means adapted to raise or lower theconveyor relative to said discharge chute, thereby to compensate'for thesize of a bag resting on the conveyor, said stitching head includingtrimming means for severing the strip of tape from the trailing edge ofthe bag in response to the advancement thereof relative to the stitchinghead and after application of said line of stitching.

2. A bag closing machine comprising, a base, a vertical column risingfrom said base, a vertical rack mounted on said column, a conveyorstructure slidably connected to said column, self-locking conveyoradjustment means on said conveyor structure including a pinion meshingwith said rack, a chute mounted above said conveyor and adapted todischarge material into the open end of a bag resting upon the conveyor,a bag stitching head slidably mounted upon said column, above theconveyor, self-locking head adjustment means connected to the stitchinghead and including a pinion meshing with said rack, said stitching headadapted to fold a strip of tape over the open upper portion of thefilled bag and to apply a line of stitching through said tape andthroughthe upper portion of the filled bag advancing on the conveyor,said conveyor adjustment means adapted to raise or lower the conveyorrelative to said discharge chute, thereby to compensate for the size ofa bag resting on the conveyor, said headt adjustment means adapted toraise or lower the stitching head relative to the conveyor, thereby tolocate the strip of tape and line of stitching with reference to theupper portion of the bag, said stitching head including trimming meansfor severing the strip of tape from the trailing edge of the bag inresponse to the advancement thereof relative to the stitching head andafter application of said line of stitching.

3. A bag closing machine comprising, a base, a vertical column risingfrom said base, a vertical rack mounted on said column, an elongatedhorizontal conveyor structure having means slidably embracing saidcolumn, a selflocking adjustment device vmounted on said conveyorstructure and including a pinion meshing with said rack, a stitcher headconnected to the column above the conveyor, said stitcher head adaptedto apply a strip of tape to the upper portion of a bag advancing on theconveyor and to apply a line of stitching through said tape and throughthe bag to seal the same, and extensible elements projecting downwardlyfrom said conveyor structure, said extensible elements adapted to beadjusted downwardly into engagement with the surface upon which saidbase is resting, whereby the conveyor structure is adapted to stabilizethe bag closing machine relative to said surface.

4. A bag closing machine comprising, a base, a vertical column risingfrom said base, a vertical rack mounted on said column, an elongatedhorizontal conveyor structure having means slidably embracing saidcolumn, a selflocking adjustment device mounted on said conveyorstructure and including a pinion meshing with said rack, a stitcher headslidably connected to the column above the conveyor, a self-lockingadjustment device mounted on the stitcher head and including a pinionmeshing with said rack, said stitcher head adapted to apply a strip oftape to the upper portion of a bag advancing on the conveyor and toapply a line of stitching through said tape and through the bag to sealthe same, and extensible elements projecting downwardly from saidconveyor structure, said extensible elements adapted to be adjusteddownwardly into engagement with the surface upon which said base isresting, whereby the conveyor structure is adapted to stabilize the bagclosing machine relative to said surface.

5. A bag closing machine comprising, a base, a vertical column risingfrom said base, a conveyor, a conveyor adjustment means connecting theconveyor to the column, said conveyor adapted to support and advance afilled open bag, a bag stitching head adjustment means connecting saidstitching head to said column in a position overhanging said conveyor,said stitching head adapted to apply a line of stitching through theupper portion of the filled bag advancing on the conveyor, said conveyoradjustment means adapted to shift the conveyor relative to the floorlevel to compensate for the height of an operator, said head adjustmentmeans adapted to shift the stitching head relative to the conveyor,thereby to locate said line of stitching relative to the upper portionof the bag, and control means interconnected with said stitcher head andengageable with the bag advancing on the conveyor, said control meansadapted to energize the stitching head in response to engagement by theleading edge of a bag advancing on the conveyor.

Angier Sept. 28, 1920 Cundall Nov. 2, 1937

1. A BAG CLOSING MACHINE COMPRISING, A BASE, A VERTICAL COLUMN RISING FROM SAID BASE, A VERTICAL RACK MOUNTED ON SAID COLUMN, A CONVEYOR STRUCTURE SLIDABLY CONNECTED TO SAID COLUMN, SELF-LOCKING CONVEYOR ADJUSTMENT MEANS ON SAID CONVEYOR STRUCTURE INCLUDING A PINION MESHING WITH SAID RACK, A CHUTE MOUNTED ABOVE SAID CONVEYOR AND ADAPTED TO DISCHARGE MATERIAL INTO THE OPEN END OF A BAG RESTING UPON THE CONVEYOR, A BAG STITCHING HEAD MOUNTED UPON SAID COLUMN ABOVE THE CONVEYOR, SAID STITCHING HEAD ADAPTED TO FOLD A STRIP OF TAPE OVER THE OPEN UPPER PORTION OF THE FILLED BAG AND TO APPLY A LINE OF STITCHING THROUGH SAID TAPE AND THROUGH THE UPPER PORTION OF THE FILLED BAG ADVANCING ON THE CONVEYOR, SAID CONVEYOR ADJUSTMENT MEANS ADAPTED TO RAISE OR LOWER THE CONVEYOR RELATIVE TO SAID DISCHARGE CHUTE, THEREBY TO COMPENSATE FOR THE SIZE OF A BAG RESTING ON THE CONVEYOR, SAID STITCHING HEAD INCLUDING TRIMMING MEANS FOR SEVERING THE STRIP OF TAPE FROM THE TRAILING EDGE OF THE BAG IN RESPONSE TO THE ADVANCEMENT THEREOF RELATIVE TO THE STITCHING HEAD AND AFTER APPLICATION OF SAID LINE OF STITCHING. 